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111.
The existence of mast fruiting has not been well documented in the Neotropics. The occurrence of a mast fruiting episode in the population of the tree Peltogyne purpurea in the Osa Peninsula of Costa Rica is described. In February and March of 2000 most of the trees of this species produced a large fruit crop, compared with 1995-1999, when the number of fruit producing trees was very low or zero and those that did bear fruit, did so at a low intensity. In contrast, the fruit crop of 2000 was massive, all trees examined produced fruits and the intensity of fruiting was maximal. There is not enough information on the event for a hypothesis to be formed because the climatic or biological cues that triggered this sporadic flowering are unknown and there is no meteorological data available for this area. Populations with this mode of reproduction may experience local extinction bacause of logging operations. 相似文献
112.
113.
Wnt/β‐Catenin Signaling Activates Expression of the Bone‐Related Transcription Factor RUNX2 in Select Human Osteosarcoma Cell Types 下载免费PDF全文
114.
Kiyoto Maekawa Masahiro Kon Kunio Araya Tadao Matsumoto 《Journal of molecular evolution》2001,53(6):651-659
Molecular phylogenetic relationships among 25 species of the wood-feeding cockroach belonging to the genus Salganea St?l (Panesthiinae; Blaberidae) in Southeast Asia were analyzed based on the DNA sequence of the complete mitochondrial cytochrome
oxidase II (COII) gene. Most basal relationships among species of Salganea are poorly resolved by both neighbor-joining and nonweighted parsimony analyses, suggesting the possibility of a hard polytomy
due to a rapid and potentially simultaneous radiation early in the history of the genus. For more apical relationships, however,
some interesting phylogenetic relationships were recognized. The monophyly of the two species groups, morio and foveolata, the former of which is distributed mainly in the Sunda lands (containing the Malay Peninsula, Sumatra, Java, and Borneo),
whereas the latter is Sulawesi endemic, was strongly supported. Based on the inferred phylogenetic patterns and recent palaeogeographic
scenario for Southeast Asia, it is suggested that a radiation of Salganea species occurred in Southeast Asia presumably in the early Tertiary, and several barriers against dispersal and gene flow,
such as the formation of straits or high mountains, have arisen from the middle Tertiary.
Received: 4 April 2001 / Accepted: 20 April 2001 相似文献
115.
Rodrigo R Bächler JP Araya J Prat H Passalacqua W 《Molecular and cellular biochemistry》2007,303(1-2):73-81
Oxidative stress may play a role in the pathogenic mechanism of essential hypertension. Lipid peroxidation can alter the cellular
structure of membrane-bound enzymes by changing the membrane phospholipids fatty acids composition. We investigated the relationship
between (Na + K)-ATPase activity, lipid peroxidation, and erythrocyte fatty acid composition in essential hypertension. The
study included 40 essential hypertensive and 49 healthy normotensive men (ages 35–60 years). Exclusion criteria were obesity,
dyslipidemia, diabetes mellitus, smoking, and any current medication. Patients underwent 24-h ambulatory blood pressure monitoring
and blood sampling. Lipid peroxidation was measured in the plasma and erythrocytes as 8-isoprostane or malondialdehyde (MDA),
respectively. Antioxidant capacity was measured as ferric reducing ability of plasma (FRAP) in the plasma and as reduced/oxidized
glutathione (GSH/GSSG ratio) in erythrocytes. (Na + K)-ATPase activity and fatty acids were determined in erythrocyte membranes.
Hypertensives had higher levels of plasma 8-isoprostane, erythrocyte MDA, and relative percentage of saturated membrane fatty
acids, but lower plasma FRAP levels, erythrocyte GSH/GSSG ratio, (Na + K)-ATPase activity and relative percentage of unsaturated
membrane fatty acids, compared with normotensives. Day-time systolic and diastolic blood pressures correlated positively with
lipid peroxidation parameters, but negatively with (Na + K)-ATPase activity. These findings suggest that the modulation of
(Na + K)-ATPase activity may be associated with changes in the fatty acid composition induced by oxidative stress and provide
evidence of a role for this enzyme in the pathophysiology of essential hypertension. 相似文献
116.
Sources of (co)variation in alternative siring routes available to male great tits (Parus major) 下载免费PDF全文
Yimen G. Araya‐Ajoy Sylvia Kuhn Kimberley J. Mathot Alexia Mouchet Ariane Mutzel Marion Nicolaus Jan J. Wijmenga Bart Kempenaers Niels J. Dingemanse 《Evolution; international journal of organic evolution》2016,70(10):2308-2321
Males of socially monogamous species can increase their siring success via within‐pair and extra‐pair fertilizations. In this study, we focused on the different sources of (co)variation between these siring routes, and asked how each contributes to total siring success. We quantified the fertilization routes to siring success, as well as behaviors that have been hypothesized to affect siring success, over a five‐year period for a wild population of great tits Parus major. We considered siring success and its fertilization routes as “interactive phenotypes” arising from phenotypic contributions of both members of the social pair. We show that siring success is strongly affected by the fecundity of the social (female) partner. We also demonstrate that a strong positive correlation between extra‐pair fertilization success and paternity loss likely constrains the evolution of these two routes. Moreover, we show that more explorative and aggressive males had less extra‐pair fertilizations, whereas more explorative females laid larger clutches. This study thus demonstrates that (co)variation in siring routes is caused by multiple factors not necessarily related to characteristics of males. We thereby highlight the importance of acknowledging the multilevel structure of male fertilization routes when studying the evolution of male mating strategies. 相似文献
117.
Miyagishi M Fujii R Hatta M Yoshida E Araya N Nagafuchi A Ishihara S Nakajima T Fukamizu A 《The Journal of biological chemistry》2000,275(45):35170-35175
CBP and its homologue p300 play significant roles in cell differentiation, cell cycle, and anti-oncogenesis. We demonstrated that beta-catenin, recently known as a potent oncogene, and CBP/p300 are associated through its CH3 region, which is a primary target of adenoviral oncoprotein E1A and various nuclear proteins, such as p53, cyclin E, and AP-1, and both are colocalized in the nuclear bodies. CBP/p300 potentiated Lef-mediated transactivation of beta-catenin, and E1A, a potent inhibitor of CBP/p300, repressed its transactivation. Furthermore, overexpression of stable beta-catenin mutant competitively suppressed the p53-dependent pathway. These may be a key mechanism of beta-catenin involved in oncogenic events underlying disruption of tumor suppressor function through CBP/p300. 相似文献
118.
Saburo Ito Jun Araya Yusuke Kurita Kenji Kobayashi Naoki Takasaka Masahiro Yoshida Hiromichi Hara Shunsuke Minagawa Hiroshi Wakui Satoko Fujii Jun Kojima Kenichiro Shimizu Takanori Numata Makoto Kawaishi Makoto Odaka Toshiaki Morikawa Toru Harada Stephen L Nishimura Yumi Kaneko Katsutoshi Nakayama Kazuyoshi Kuwano 《Autophagy》2015,11(3):547-559
Cigarette smoke (CS)-induced mitochondrial damage with increased reactive oxygen species (ROS) production has been implicated in COPD pathogenesis by accelerating senescence. Mitophagy may play a pivotal role for removal of CS-induced damaged mitochondria, and the PINK1 (PTEN-induced putative kinase 1)-PARK2 pathway has been proposed as a crucial mechanism for mitophagic degradation. Therefore, we sought to investigate to determine if PINK1-PARK2-mediated mitophagy is involved in the regulation of CS extract (CSE)-induced cell senescence and in COPD pathogenesis. Mitochondrial damage, ROS production, and cell senescence were evaluated in primary human bronchial epithelial cells (HBEC). Mitophagy was assessed in BEAS-2B cells stably expressing EGFP-LC3B, using confocal microscopy to measure colocalization between TOMM20-stained mitochondria and EGFP-LC3B dots as a representation of autophagosome formation. To elucidate the involvement of PINK1 and PARK2 in mitophagy, knockdown and overexpression experiments were performed. PINK1 and PARK2 protein levels in lungs from patients were evaluated by means of lung homogenate and immunohistochemistry. We demonstrated that CSE-induced mitochondrial damage was accompanied by increased ROS production and HBEC senescence. CSE-induced mitophagy was inhibited by PINK1 and PARK2 knockdown, resulting in enhanced mitochondrial ROS production and cellular senescence in HBEC. Evaluation of protein levels demonstrated decreased PARK2 in COPD lungs compared with non-COPD lungs. These results suggest that PINK1-PARK2 pathway-mediated mitophagy plays a key regulatory role in CSE-induced mitochondrial ROS production and cellular senescence in HBEC. Reduced PARK2 expression levels in COPD lung suggest that insufficient mitophagy is a part of the pathogenic sequence of COPD. 相似文献
119.
Francisco Villanueva Hector Araya Pedro Briceño Nelson Varela Andres Stevenson Sofia Jerez Fabian Tempio Jonas Chnaiderman Carola Perez Milena Villarroel Emma Concha Farzaneh Khani Roman Thaler Flavio Salazar-Onfray Gary S Stein Andre J. van Wijnen Mario Galindo 《Journal of cellular physiology》2019,234(8):13659-13679
120.
The alpha and beta chains of White-Throated Capuchin (Cebus capucinus) hemoglobin were separated and digested by trypsin. The tryptic peptides were isolated and sequenced by conventional methods. The peptides in each chain were aligned by the homology of their sequences with those of human adult hemoglobin. The primary structures thus deduced are compared with those of other primate hemoglobins, and we discuss the molecular evolution of hemoglobins, in particular the rate of evolution in New World monkey hemoglobins. 相似文献